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排序方式: 共有3689条查询结果,搜索用时 31 毫秒
31.
Takashi Minase Minoru Ogasawaea Takanori Kikuchi Hideaki Hirai Akira Suzuki Chieko Nishio Katsuhiro Ogawa Kokichi Kikuchi Michio Mori 《Pathology international》1985,35(3):711-721
A case of lymphomatoid granulomatosis (LYG) involving the lungs, skin, stomach, and possibly the left kidney in a 60-year-old man is presented. The infiltrates in the lungs, stomach, and skin showed a polymorphic appearance, and consisted predominantly of lymphocytes of mature and blastic form and of a few neutrophils, plasma cells, and histiocytes. Most lymphoid cells showed irregularly shaped nuclei and clustered dense bodies, characteristics indicative of T lymphocytes. An immunohistochemical study confirmed the T cell origin of the lymphocytes; i.e. they were positive for Leu-1, Leu-3a and la-like antigens but negative for Leu-2a antigen and the antibodies against light chains. The homogeniety of the major population of infiltrates in LYG indicates that at least some forms of LYG may be neoplastic or pre-neoplastic lymphocytic disorders which may ultimately progress to malignant lymphoma. ACTA PATHOL. JPN. 35 : 711–721, 1985. 相似文献
32.
Inferring alternative splicing patterns in mouse from a full-length cDNA library and microarray data
Kochiwa H Suzuki R Washio T Saito R Bono H Carninci P Okazaki Y Miki R Hayashizaki Y Tomita M;RIKEN Genome Exploration Research Group Phase II Team 《Genome research》2002,12(8):1286-1293
Although many studies on alternative splicing of specific genes have been reported in the literature, the general mechanism that regulates alternative splicing has not been clearly understood. In this study, we systematically aligned each pair of the 21,076 cDNA sequences of Mus musculus, searched for putative alternative splicing patterns, and constructed a list of potential alternative splicing sites. Two cDNAs are suspected to be alternatively spliced and originating from a common gene if they share most of their region with a high degree of sequence homology, but parts of the sequences are very distinctive or deleted in either cDNA. The list contains the following information: (1) tissue, (2) developmental stage, (3) sequences around splice sites, (4) the length of each gapped region, and (5) other comments. The list is available at http://www.bioinfo.sfc.keio.ac.jp/intron. Our results have predicted a number of unreported alternatively spliced genes, some of which are expressed only in a specific tissue or at a specific developmental stage. 相似文献
33.
Konno A Hoshino Y Terashima S Motoki R Kawaguchi T 《Clinical & experimental metastasis》2002,19(1):61-70
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer. 相似文献
34.
Sehata S Maejima T Watanabe M Ogata S Makino T Tanaka K Manabe S Takaoka M 《Toxicologic pathology》2002,30(3):328-338
The carcinogenic potential of chloroform was evaluated in a short-term carcinogenicity testing system using CB6F1 rasH2-Tg (rasH2-Tg) mice. Chloroform was administered to rasH2-Tg males at doses of 28, 90, or 140 mg/kg and rasH2-Tg females at 24, 90, or 240 mg/kg by oral gavage for 26 weeks. Wild-type (non-Tg) male and female mice received doses of 140 mg/kg and 240 mg/kg, respectively. N-methyl-N-nitrosourea was administered to rasH2-Tg mice by single intraperitoneal injection (75 mg/kg) as a positive control. In both the rasH2-Tg and non-Tg mice, there was no significant increase in the incidence of neoplastic lesions by chloroform treatment. The incidence of hepatocellular foci in the rasH2- and non-Tg females receiving 240 mg/kg was increased. Forestomach tumors and malignant tumors occurred in most of the rasH2-mice in the positive control group. Swelling or vacuolation of hepatocytes, a toxic change induced by chloroform, occurred in both the rasH2-Tg and non-Tg mice. It is concluded that chloroform, a putative human noncarcinogen, did not show evidence of carcinogenic potential in the present study using rasH2-Tg mice. This study suggests that the rasH2-Tg mouse model may not be appropriate for detecting nongenotoxic carcinogens. However, the sensitivity of rasH2-Tg mice to nongenotoxic carcinogens should be assessed with consideration of the results from the other ILSI-HESI project studies. 相似文献
35.
GP7 can induce apoptotic DNA fragmentation of human leukemia cells through caspase-3-dependent and -independent pathways 总被引:2,自引:0,他引:2
GP7 (4-[4"-(2",2",6",6"-tetramethyl-l"-piperidinyloxy)amino]-4'-demethyl epipodophyllotoxin), a new spin-labeled derivative of podophyllotoxin, is a promising anticancer drug of podophyllotoxin class. The primary effect of GP7 is the anticancer activity on transplanted mouse tumors and cultured tumor cells. However, its molecular mechanism of action is still obscure. In this study, we investigated the activity of GP7 to induce apoptosis in human leukemia HL-60 and Jurkat cells. Apoptosis was determined by detection of DNA fragmentation in agarose gel electrophoresis. GP7 induced apoptotic DNA fragmentation of HL-60 and Jurkat cells in time- and dose-dependent manner. We further investigated the activity of caspase-3 in GP7-induced apoptotic DNA fragmentation of HL-60 and Jurkat cells. GP7 also induced time- and dose-dependent caspase-3 activation in both cell lines, and the kinetics of caspase-3 activation induced by GP7 was well correlated with that of apoptotic DNA fragmentation. To determine the role of caspase-3 in GP7-induced apoptotic DNA fragmentation, we examined the effect of specific caspase-3 inhibitor, Ac-DEVD-CHO, on GP7-induced apoptotic DNA fragmentation. Ac-DEVD-CHO prevented GP7-induced caspase-3 activation in both HL-60 and Jurkat cells, however, it only inhibited GP7-induced apoptotic internucleosomal DNA fragmentation in HL-60 cells. We then employed L-carnitine to investigate the role of caspase-3 in GP7-induced apoptotic DNA fragmentation. L-carnitine treatment prevented GP7-induced caspase-3 activation in both cell lines in a dose-dependent manner. Similar to Ac-DEVD-CHO, L-carnitine only inhibited GP7-induced apoptotic internucleosomal DNA fragmentation in HL-60 cells. These findings suggest that GP7 exerts an anti-leukemic effect by both caspase-3-dependent and -independent apoptotic signaling pathways. 相似文献
36.
Effects of magnesium on prostacyclin synthesis and intracellular free calcium concentration in vascular cells. 总被引:3,自引:0,他引:3
Kazuo Satake Jong-Dae Lee Hiromasa Shimizu Hiroyasu Uzui Yasuhiko Mitsuke Hong Yue Takanori Ueda 《Magnesium research》2004,17(1):20-27
This study investigated the effects of extracellular magnesium concentration ([Mg2+]e; 0.3-3 mM) on intracellular free calcium concentration ([Ca2+]i) and prostacyclin (PGI2) production in cultured human umbilical vein endothelial cells (HUVEC) and vascular smooth muscle cells from rats (VSMC) under basal and agonist-stimulated conditions. We used histamine as agonist which increases [Ca2+]i and PGI2 production in HUVEC, norepinephrine in VSMC. [Mg2+]e dose-dependently increased basal and agonist-stimulated PGI2 production in both cells. [Mg2+]e dose-dependently reduced basal [Ca2+]i in VSMC, but did not influence in HUVEC. In both cells, increasing [Mg2+]e reduced agonist-stimulated [Ca2+]i responses. Furthermore, [Mg2+]e dose-dependently reduced agonist-stimulated [Ca2+]i in Ca(2+)-free buffer, indicating intracellular Ca2+ release. In VSMC, 10(-6) M diltiazem and 10(-7) M nifedipine, Ca2+ channel blockers, reduced agonist-stimulated [Ca2+]i as well as 3 mM Mg2+, but did not affect PGI2 production. [Mg2+]e amplified dose-dependently arachidonic acid-induced PGI2 production in both cells, suggesting the activation of cyclooxygenase and/or PGI2 synthetase. Our results suggest that [Mg2+]e influences intracellular Ca2+ mobilization of not only vascular smooth muscle cells but also endothelial cells by inhibiting both Ca2+ influx and intracellular Ca2+ release. [Mg2+]e enhances PGI2 production in both types of cells, although the mechanism is likely to be independent from Ca2+ mobilization. 相似文献
37.
Morphological changes in the mouse sublingual gland parenchyma subjected to parasympathetic nerve block were investigated. Mice were subjected to unilateral resection of the chorda tympani, near its point of joining with the lingual nerve. After 1, 2, 3, 5, 10 or 20 weeks, the mice were killed and their sublingual glands were removed and processed for light and electron microscopy. Two weeks after resection, the space between the adjoining lobules of the glands on the treated side began to be expanded, and by 10 weeks were 10 times the size of the spaces in the glands of the untreated mice. Three weeks after resection, the lobule area decreased to about 72% of the area of glands in the untreated mice and the acinus area to about 52%. However, no significant difference was seen between the numbers of acini in each group. Electron microscopy showed that the glands on the treated side contained fewer secretory granules than the glands in the untreated mice, though there was no difference in size. Neither the lobules of the glands on the treated side nor those of the glands of the untreated mice contained many TUNEL-positive cells. These findings suggest that following parasympathetic nerve resection, mouse sublingual gland acinar cells undergo atrophy with a reduction size rather than cell death. 相似文献
38.
Mika Ogata Akinori Sukuya Chizuko Sugizaki Kaori Ikematsu Takanori Imai Hiroshi Tachimoto Motohiro Ebisawa 《Arerugī》2008,57(7):843-852
OBJECTIVE: We investigated the usefulness of skin prick test (SPT) for the diagnosis of egg white (EW) allergy in infants with atopic dermatitis who showed negative to EW CAPRAST, and followed up the EW-CAPRAST in this study. SUBJECTS AND METHODS: Data of negative SPT using Bifurcated needle (BN) were analyzed from the data of 202 atopic dermatitis infants, who had received SPT from January in 2001 to April in 2005. From the negative SPT value (average and standard deviation) positive SPT value was obtained. Among 202 cases, 89 suspected-egg allergy infants with negative IgE CAPRAST against EW at the time of first visit were recruited to examine the usefulness of SPT. Positive conversion of EW-CAPRAST was checked in 78 cases (65: egg allergy+, 13: egg allergy(-)) who had been followed up in our outpatient clinic. RESULTS: Range of negative SPT control value (mean+2SD) using BF among infants could be set as less than 2 mm for wheal and/or 5 mm for erythema. Among 89 suspected-egg allergy infants with negative EW-CAPRAST, 72 infants (80.9%) were diagnosed as egg allergy by the combination of elimination and provocation test, interestingly 39 infants (54.2%) showed positive SPT results. In the follow up study of 78 negative EW-CAPRAST cases, 47 EW-CAPRAST out of 65 egg-allergy cases turned positive later infantile period (mean EW-CAPRAST: 9.6+/-16.7 Ua/ml at 9.9+/-5.6 months old). EW-CAPRAST of 7 cases in 13 non-egg allergies also turned positive in the follow up, however EW-CAPRAST titer was relatively lower compared to that of egg allergies (1.1+/-1.5 Ua/ml at 13.3+/-2.6 months old). CONCLUSIONS: We experienced fairly number of atopic infants with negative EW-CAPRAST at the first outpatient visit, who were later diagnosed as egg allergy. In about half of these cases, SPT egg-allergy infants, three quarter of EW-CAPRAST turned positive around 10 months old. EW-CAPRAST of atopic infants without egg allergy also turned transiently and slightly positive. In the conclusions, SPT seemed to be more useful than EW-CAPRAST for the diagnosis of egg allergy in early infantile period, however provocation test should be required for the definitive diagnosis in suspected-egg allergy infants without any proof of egg-sensitization. 相似文献
39.
Dr Takanori Kawaguchi Tomohisa Ono Hironao Wakabayashi Seiji Igarashi 《Clinical & experimental metastasis》1994,12(3):203-212
Rat ascites hepatoma AH7974 cells strongly expressed antilaminin antibody-reactive substances (laminin-like substances) andGriffonia simplicifolia isolectin B4 (GS)-reactive carbohydrate (alpha)-d-galactose; alpha-Gal) on their cell surface. The alpha-Gal expression was not apparently influenced by the pretreatment of cells with methanol. The cell membrane laminin-like substances had approximate molecular weights of 150, 62 and 56 kDa in denaturating reducing conditions, of which the 62 and 56 kDa bands were stained with GS. The cell membrane molecules bearing alpha-Gal were 62 and 56 kDa and were stained with antilaminin antibody. Therefore, the major molecules bearing alpha-Gal residues of AH7974 cell membrane are considered to be laminin-like substances. To determine the role of the substances in metastasis, we selected four cell lines (74AD, 74AD-f, 74FL, 74FL-a) from AH7974 in culture. 74AD and 74FL-a are adherent lines and 74AD-f and 74FL are floating lines. All of these cell lines strongly expressed laminin-like substances, but a marked difference was found in expression of alpha-Gal, which was most strongly expressed by 74FL, followed by 74AD, and rarely by 74AD-f and 74FL-a; the staining intensity was positively correlated with their experimental lung-colonizing potential. Cell membrane laminin-like substances were 200, 97, 62, 56 and 46 kDa and among them 62 and 56 kDa molecules were glycosylated with alpha-Gal. The pretreatment of 74FL cells with antilaminin antibody or with human type A serum (containing natural antibody to alpha-Gal epitope) depressed remarkably the lung-colonizing potential of the cells. These results suggest that the expression of 62 and 56 kDa laminin-like substances with alpha-Gal residues on tumor cell surfaces is one of the determinants associated with lung-colonizing potential of these cells. 相似文献
40.
Hanada H Takeoka K Nomura T Moriyama T Kanakura Y 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(4):297-302
CA19-9 widely used as a tumor marker of the pancreas and a bile duct. There are a number of reports which describes the measured value discrepancies between RIA and non-RIA kits. RIA results also have shown lack of the linearity over 70 U/ml when the samples are diluted. The pH condition at assay reaction for RIA had been suggested as the major reason, it has been denied by the results from the same pH condition at assay reaction used by COBAS CORE CA19-9 EIA II. On the other hand, the lack of RIA antibody titer is indicated for the discordant results by changing the sample volume to reagent volume ratio in the reaction. Our further investigation also indicates that the specific Lewis blood type, i.e. Le (a-b+), shows the linearity issues by RIA. The discrepancies are not caused by the reaction pH, but the amount of the antibody used in the RIA kit is closely associated. Considering the CA19-9 antibody nature used in RIA kit, which covers broad molecular range, users need to pay more attention to setting up each laboratory's measuring range. 相似文献